Efficacy and Safety of the PreserFlo MicroShunt in Asian Patients With Glaucoma: Two-year Results

Précis: This prospective study demonstrates that the PreserFlo MicroShunt effectively reduces IOP and medication burden over 24 months in Asian patients with POAG, although risk of complete success failure was higher in combined cataract surgery. Background: Glaucoma is characterized by progressive and irreversible vision loss due to optic nerve degeneration. Lowering intraocular pressure (IOP) remains the mainstay of glaucoma treatment. The PreserFlo MicroShunt (Santen Pharmaceutical Co.) is a form of minimally invasive bleb surgery. Objectives: We investigate the efficacy and safety of PreserFlo MicroShunt device in Asian patients with primary open angle glaucoma over a 24-month postoperative period. Design: A prospective, single-arm study of subjects with POAG receiving the PreserFlo MicroShunt surgery with or without concurrent cataract surgery. Methods: Primary outcome at 2 years was complete success (IOP ≥20% reduction without medications and IOP<22 mm Hg if baseline IOP>21 mm Hg). Results: Ten eyes underwent PreserFlo MicroShunt surgery, and 17 eyes underwent combined phacoemulsification and PreserFlo MicroShunt. Mean baseline IOP was 22.1 mm Hg, and the median baseline medication load was 3.0. At 6, 12, and 24 months, the complete success rate was 55.6%, 48.1%, and 37.0%, respectively. Qualified and complete success at 6, 12, and 24 months was 81.5%, 74.1%, and 63.0%, respectively. Mean reduction in IOP was 7.9, 6.0, 7.1 mm Hg at POM6 ( P <0.001), POM12 ( P =0.020), and POM24 ( P <0.001). Reduction in median number of medications was from 3 to none at 6, 12, and 24 months ( P <0.001). The risk of complete success failure was significantly higher in the combined group compared with the standalone (HR: 10.08; 95% CI: 2.26–45.07). One eye required open revision, 2 eyes required trabeculectomy, and 5 eyes had bleb needling or injection with antimetabolite. Conclusions: Our study demonstrated that the PreserFlo MicroShunt effectively lowered IOP and medication burden in Asian eyes with POAG.